U.S. patent application Ser. No. 936,338 discloses a needle assembly which has the advantages of housing a needle so that the user is protected from accidental puncture. In that apparatus, a syringe is coupled to a housing which contains the needle and covers it unless intentional steps are taken to cause the point to be exposed during connection to a medication container, a medication delivery apparatus or during intravenous or transcutaneous injection.
However, that application does not treat the problems associated with contact of the health care provider with the blood or serum of the patient during or after an injection. Since contact with the blood or serum of a person infected with certain contagious viruses can be highly dangerous, it is important to avoid such contact.
Normally, before an injection, the area of the skin to be punctured is cleaned with a substance such as alcohol. Following the injection, the needle puncture bleeds to some extent and is typically covered with sterile cotton, sometimes held in place with someone's finger or a small adhesive bandage. A danger exists that accidental contact with the blood emanating from the puncture can occur at that stage of the process.